Micra Starting Problem - ScottieDog
Folks,

I know this is a common problem (but I can't find out how to search the back room database effectively yet)...

Since it was 2...My Micra Twister 1.0L (98/R). Has had the following problem:

In the morning (almost exclusively) if it doesn't start first time, it doesn't start!

Luckily, I've always lived on a street with a hill and I can bump start it 100% of the time (which is fine unless I stall it right at the bottom of the hill). Point here is it would always catch and start.

Last 2 days, however, it wouldn't catch first time and wouldn't bump either (got the wife to give me as tow start yesterday which was a funny experience as she had never done it before - big terrano pulling little micra all over the road).

Wish I had got something done in the warranty. However, found several hints about resoldering throttle control PCBs and suggestions about air flow sensors. Would appreciate some sound advice on adjustments or which bits to replace (hopefully I can get them from the local scappie).

Thanks...
Micra Starting Problem - mare
i had a S reg Twister - nice little car.

Anyway i managed to flood mine twice, but in winter. I don't know what your specific problem is but there are past threads on Micra's and poor starting. Try this thread for inspiration:

www.honestjohn.co.uk/forum/post/index.htm?t=21817

Hopefully Aprilia'll be along shortly

Micra Starting Problem - Chris S
It seems to be a common problem. This might help www.honestjohn.co.uk/forum/post/index.htm?t=37173
Micra Starting Problem - ScottieDog
Thanks folks...

Looks like several tracks to follow:

Throttle body / air mass meter
Wiring loom mod to harness
Checking fuses at battery
Trying to start by removing fuel pump fuse (anyone know which fuse it is?).

Thanks again...
Micra Starting Problem - RichardM
Fuse is listed on the fusebox cover which is above and right from the accelerator pedal.
Micra Starting Problem - ScottieDog
Thanks...

Checked for corroded fuses beside battery (all good)...
Removed fuse for fuel pump and wouldn't start (although gave a few hints that it might). Started anyway after a very short tow. Pulled fuse again to check fuel cuts out and it did.
Carried out dry joint resolder to throttle body (checked continuity first and OK, but had cover off so resoldered anyway). Leaving the throttle body overnight to allow the silicone sealer to cure on the electronics cover I removed.

Have inquired about harness mod from Nissan (£9.50). Can anyone tell me where it is to be fitted? (if that doesn't work it's off to the scrappies for a throttle body).

Thanks again...
Micra Starting Problem - RichardM
From memory the harness goes on the right side of the block, about 8" down. Not much of a description I know, but it helps if you have a Haynes manual. In my case the harness made no difference, however. As Aprilia and others suggested in past threads about this, the flooding problem is reportedly caused by the coolant temperature sensor which is what I would be looking at if I were you.
Micra Starting Problem - Aprilia
I wouldn't muck about with this. Replace temp sensor and piece of loom. Less than £30 and it should cure your problem. Obvioously HT system need to be in good shape.
Micra Starting Problem - ScottieDog
Well folks,

Fitted loom and no difference to starting initially....Decided to follow Aprilia's suggestions and...

Plugs were black and wet (probably from all the starting attempts). Replaced these and rotor arm / distributer cap (contacts pretty worn) and fired up first time. Switched off then restarted again repeated lots of times and looks like the loom may have helped with the over-fuelling on starting problem (temp sensor values also checked out OK). Nissan said they had a tech bulletin from 1999 detailing a cold-start overfuelling problem for cars around the age of mine (98/R) and the introduction of the wee loom upgrade.

Anyway still off the road due to the fact I have botched the throttle body resoldering procedure. Whatever I have done has caused some kind of problem and the car will only rev up to (probably as theres no Tacho) 3 or 4k RPM. If I go above this revs start to go unstable (sort of a throbbing woob..woob..woob sound) and car has no power if accelerating anything other than gently (and could only hit 20mph going up a slight hill). It's definately something I've done 'cos the car had been running fine during the runs I did after the tow starts.

Heading to scrappies today (feeling like a bit of an idiot)....one suggestion...don't mess with the throttle body unless you've nothing else left to try.

Will let U all know if I get back on the road.

Thanks again...
Micra Starting Problem - Aprilia
Yes, sounds like the throttle body has been cocked-up. Can you 'desolder' (using a solder-sucker) the connections in the throttle body and then carefully re-make the joints with some good quality solder (not the dreadful 'lead-free' stuff) using a 'professional standard' soldering iron. Maybe a local TV/radio repair place could do this for you.
I think you will really struggle to find a good throttle body in a breaker's yard.
Micra Starting Problem - ScottieDog
Aprilia...

U R so right...

Got a throttle body today and it had a bash on the flow meter cover (i.e. the one I had removed on my original to do the solder job). Said to the Scrappie who offered to swap it for another of it was no good after I tried it.

Same fault with the throbbing at mid-revs. However, a few minutes into warm up it didn't stop and stutter mid range (it let me give it a good few revs), left it for a few minutes and it was back to stuttering (tick-over and low revs are smooth).

A wee bit of jiggery-pokery swapping connectors on to my original throttle body (but disconnected), I observed that the engine would stall if I opened either throttle. Am I correct in deducing that the engine management system will only allow more fuel through if it sees an increase in air flow and throttle position? If my assumption is correct (and the air flow meter is showing reduced or restriced flow) this would explain why I can't get the revs beyond mid-range). So no matter how much I open the throttle it will only give me the amount of fuel for the airflow it thinks it has!

Continued in next post
Micra Starting Problem - ScottieDog
Continued from previous

Getting a bit over ambitious for a novice but tried a few more things in case they had anything to do with the problem.

Checked the temp sensor (again), swapped the lambda sensor, blanked the venturi (to brake servo?) and no change. Pulled 1 injector connector off and engine ran but rough (just to see if it was a cylinder related problem). Gave the wiring good visual check (especially pot and air flow connectors).

Can get a new unit for #320 plus vat (probably more than the current market value of my Micra). Saw mentions of reconditioned ones for around #175 (anyone know where I could get one in central Scotland?) I'm not a mechanic but this is becoming interesting (although I'd happily give up interesting for a running car)...

Will go back to scappies to see if he will swap me another one...

Will update soon...
Micra Starting Problem - Aprilia
There's a place in Nottingham does them for £100, and of course BBA-Reman.

However these are cheaper on Ebay:

Item 270022241901

or this one for about £40 - item 280021446167
Micra Starting Problem - ScottieDog
Folks,

Thanks for all your help...The Silver-Dart lives again...

Swapped in another throttle body from the scappies and running fine now.

Best regards to you all...

ScottieDog